Web materials of various types have heretofore been wound into successive rolls by using apparatus which supports the roll of web material until the roll reaches a final size at which time the web is severed and a new roll is formed. Examples of such devices include U.S. Pat. Nos. 3,199,393, 3,485,121, 4,000,863 and 4,475,696 which are commonly owned with the present invention. For many thin and non fibrous webs, such as foam and paper, a relatively simple serrated blade cutter, such as shown in U.S. Pat. No. 4,475,696, will quickly and easily cut through the web in a uniform cross cut. However, for thicker or fibrous webs, the serrated blade tends to shred the web and not provide a clean cut.
To cut these thicker or fibrous types of webs, a severing device including power driven endless cutter chain was developed to provide an instantaneous cross cut. As explained in detail in U.S. Pat. Nos. 3,199,393, 3,485,121 and 4,000,863, the cutter chain includes a series of spaced apart sharp cutting elements which shear through the web when the severing device is raised into and through the path of the web. Such severing devices have been very successful in providing a clean, virtually instantaneous cut in the web. However, in the process of cutting and forming a series of successive rolls, the cutter chain will stretch and increase in length over time. Presently, the operator must stop the winding machine and manually tighten the chain typically by repositioning a cutter chain sprocket.
In many operations, the winding machine is operated continuously, twenty-four hours a day. Shutting down the winding machine for such an adjustment can be very expensive and typically takes several hours before the service man may get to and complete the adjustment. As a result, some operators have put off adjusting the slack in the chain until the chain has sagged to such a degree as to engage underlying portions of the winding machine destroying the chain and other equipment on the winding machine.
Accordingly, it is an object of the present invention to provide means to adjust the tension of the cutter chain during operation of the winding machine and thus maintain the chain from becoming unduly slack so as to avoid the need for manual adjustment and to thereby avoid the disadvantages of the prior art as discussed above.
It is a further object of the present invention to provide means for incrementally adjusting the tension of the cutter chain as the same stretches and increases in length during operation of the winding machine.
It is a further object of the present invention to provide a process of operating a winding apparatus so as to prevent an unduly slack cutter chain by adjusting the tension of the same during operation of the winding apparatus.